Dogging mechanism



Jan. 5, 1932'. G, TANNER 1,839,713 y .DOGGING MECHANI SM Filed May 31, 1930 2 Sheets-Sheet 2 ZSnventor @50H65 72H/YER- Gttomeg Patented dan. 5, 193.2

arras G-GRG-E TANNER, F SANDPOINT, IDAiI-IO DQGGING MECHANISM:

Application inea May 31, 193e. serial No. 458,524.

My present invention relates to improvements in dogging mechanism forsaw mill set works. The invention is embodied with the transversely sliding knee which is mounted on the longitudinally moving head block or beam of the saw mill set works. The dogging mechanism includes a pairV of dogs and means are provided whereby the dogs may be moved vertically as well as horizontally with relation to the knee and to the zontal movement of the log to be sawed, and motive Huid operating devices are utilized for accomplishing the movements of the clogging mechanism. Means are provided for cushioning the horidogging mechanism, and also for-resiliently supporting the mechanism, as will be described. Means are also provided for taking up wear of operating parts to insure at all times a compact arrangeo ment of the operating parts, and a durable, strong, and efficient mechanism is provided for rigidly holding the log in position to insure accuracy in cuts of the timber.

The invention consists in certain novel i combinations and arrangements of parts as will hereinafter be more fully set forth and claimed. In the accompanying drawings I have illustrated one complete example of the physical embodiment of my invention wherein the parts are combined and arranged according to the best mode l have thus far devised for the practical application `of the principles of my invention. Y K

Figure 1 is a vertical sectional view through one of the knees, showing the Ydog holder also in section, and illustrating the arrangement of the dogs.

Figure 2 is a face view of one of the interchangeable wear blocks or plates, and Figure 3 isa face-view of another form of interchangeable block or plate used in the mechanism.

Figure 4 is an exterior view of one of the kneeswith the clogging mechanism mounted thereon and therein, and showing alsofother parts of the carriage to indicate the relation of parts.

Figure 5 is a tace view of the knee in Figure 4, other parts of Figure 4v being omitted.

Figure 6 is a top plan view of the dogI holder showing its relation to the supporting and guiding bar for the holder, the bar being shown in section.

Figure 7 is a detail view showing one of theV anti-friction rollers between the dog holder and a face plate of the knee. n

In order that the general arrangement and relation of parts may readilybe understood reference should first be had to Figure 4 where the usual head block or beam 1, forming .part of the saw mill carriage, is shown, and the carriage travels toward and away from the saw 'with v.its wheels 2` rolling on the tracks or rails 3.

The sliding knee 4v reciprocatestoward the right and left in Figure 4 transversely of the carriage between cutting or sawing operations, and this knee, which base or bottom plater, and a pair of spaced face plate 6 that are secured, as by screws 7 to the side walls of the knee. Y

'The dog holder 8 is disposedrin upright position back of the face plates and between the side walls of the knee, and the holder is fashioned with two vertical slots 9, and 10, the former as housings for the dogs 41 and 42,.and the side slot 10 for co-action with the upright guidebar 13.

ltal position, and this face plate is resiliently `supported from the base plate 5 of the knee by means of a-headed pin'or-'bolt 15, with its head 16 in position to slide on the upperface of the plate 5. The pin projects loosely into a socket 15 17 coiled about the pin *and located between the headY of the pin and the wall of the socket provides'a resilient support for the guide bar 10Q' when it is locatedat its lowermost position.

is hollow, has a of the plate 14, and a springV The upper end of the dog holder is closed VS0 vwith relation to its of the holder and at its upper end a hollow i boss 22 is fashioned to receive the stem, and lock nut 21 secures the stem to the boss in order that the holder may be moved with the stem. At its lower end the air cylinder is secured as by bolts 18 the guide bar, and it will thus be apparent that the cylinder is rigid with the guide bar while the holder is rigid with the stem and piston. Air may be admitted under pressure through port 19 to elevate the holder, or pressure may be permitted to escape through the port to permit lowering of the holder and its dogs.

Two pairs of anti-friction rollers as 23 are carried in sockets 24 located at opposite sides of the slot 9 of the holder, and these sockets, as best seen in Figure 7 have open fronts in order that the rollers may engage and roll on the inner faces of the two face plates as the holder vertically reciprocates. Y

In addition to the vertical movement of the dog holder, the latter, together with its guide bar, plate 14 and cylinder 18, also has horizontal movement, and this latter movement is accomplished by the use of air under pressure in the air cylinder 25 that is secured as by bracket 26 to the outside face of the knee 4.

Y Two bell crank levers 27 and 28 are supported on the pivot pins 29 and 30, the former near the top of the knee and the latter near the bottom of the knee, and these two levers are connected by link or rod 31 to move in unison, exterior of the knee.

The bell crank levers are pivotally connected to the guide-bar of the dog holder by trunnions 32 and 33, the former projecting laterally from the bar above the knee, and the Alatter 'projecting laterally of the bar through an arcuate slot 34 in one wall of the knee. The connections betweenthe bell crank levers and the guide bar are such that the latter may be shifted or swung on the pivots 29 and 30 to project or retract the dogs with relation to the face plates 6 kof the linee.

As best seen in Figure 4 the air cylinder 25 has j a piston 35 (dotted lines) reciprocahle therein, d the stem 36 of the piston projects through the upper end of the cylinder. At its upper end the stem has a lshackle 37 that is pivoted at 38 tothe long arm of the bell crank lever 27, and the shackle, which is L-shaped, has a hole therein for the stem, and lcck nuts 39 are emto the plate 14 of ployed to lock the shackle rigidly on the stem.

The admission and eXit of air under pressure to and from the cylinder 25 is properly controlled by usual control means `for swinging the dog holder, and it will be apn parent that the spring 17 is instrumental in cushioning the movement of the holder and other parts rigid therewith or carried therewith.

The upper dog 40 is fashioned with a point or tooth 41, and the lower dog 42 has a special tooth 42', and both dogs, as shown may be projected or retracted through the front of the knee.

The upper dog 49 is supported in the slot 9 or housing of the dog holder, and the dog is fashioned with a slot 44 that permits relative movement of the dog. At its upper end the dog is fashioned with a cam edge or face 45 that bears against a complementary cam face 46 formed. in the holder, and spaced ears 47 enclose the cam head 45 of the dog. An expansion spring 48 is connected at one end to the dog and at its other end to the holder, the tendency of the s )ring being to pull down on the upper end of the dog and project its point 41.

The lower dog 42 is fashioned with a head 49, and a spring rod 50 is head within the holder. A spring` 51 is coiled about the rod and interposed between a collar 52 fixed on the rod and a supporting pin 53 rigid with the holder, the pin being perforated for the rod, and the per? forated pin forms a guide for the rod.

The lower dog is curved as shown and it is supported in the holder by a number of pivoted to the wear blocks 54, here shown as three in num- A ber and of square shape, with a hole 55 iny the blocks.

As best seen in Figure 3 the hole 55 is set eccentrically in the square block in order that the four faces of the block are at varying distances from the center of the hole. These blocks are supported on pins 56 that extend transversely through one side wall of the dog holder and across the slot or housing 9 of the holder. ln addition tothe square blocks, I utilize another l block as 57 having somewhat of a heart shape, and provided with an opening or hole 58. This hole, as best seen in Figure 2 is arranged off the center of the longitudinal axis of the block, and one convex face of the block is farther from the center of the hole than the opposite convex face.

The blocks 57 is located in ,front of the lower dog, just within the face plates 6, and it occupies the width of the slot 9 as do also vsquare blocks 54 and the heartshape block 57. The dog is permitted to slide between urn.,

the blocks 54. The wear block 57 is supthe blocks, and the spring 51 tends to hold the dog down, with its head 49 resting on one of the blocks 54. l

The lower dog is designed for use with logs of small diameter and it is so arranged within the wear blocks as to draw the log toward the knee as the dog penetrates the log. Thus, when the holder is lowered to engage the point 42 of the dog with `the log, the upward pressure on the curved dog is receivedV by the-'convex wear face of the block 57, and lateral thrust is taken up by the two square wear blocks 54 at the left side or rear of the dog. The upward give of the dog against the tension of spring 51 pulls the tooth 42 toward the knee, and thereby the log is drawn up against the face plates of the knee, and there held by the tooth to insure an accurate cut of the log.

The upper dog, which is used for a log of larger diameter, also draws the log in toward the knee as its point 41 penetrates kthe log. This pull or draw on the log is accomplished by the co-acting cam portions 45 and 46, as the dog is moved upwardly and inwardly, and guided by the pin and lslot arrangement 43 and 44. As the dog is pushed upwardly, the cam action swings the head or upper end of the dog to the right in Figure 1, and of course the tooth or point of the dog is swung to the left. After the dog is released from the log the spring 4.8 returns `the dog to normal position.

l/Vith respect to dog 42 it will be apparent that as the edges of the dog wear, or if the wear edges of the blocks 54 and 57 become worn, thus permitting undesirable looseness of the dog in its bearings, the blocks may be turned so that a fresh wear edge ofthe blocks may be frictionally engaged bythe concave and convex edges of the dog.

A, fixed dog 60, as usual, is carried at the lower end of the knee, and performs its functions in Vwell known manner.

At its rear, the dog holder is provided Y with means for retaining the dogging mechanism, including the dog holder and guide bar against looseness, and tov absorb or cushion shocks, as well as to take up wear. This cushion includes a vertically vsuspended spring blade or resilient plate 61 that is sup-` ported from and infront of a transverse partition 62 of the knee. A

At its lower end, the partition 62, which is rigid with the knee is provided with` an olfset lug 63, and a link 64 joins the cushion with the lug by pivot pins 66 and 65. The lower end of the spring bladelor cushion 6l bears against the rear edge of the'plate 14V of the cylinder 18, and `it will be apparent that as the plate 14 is moved to the left in Figure 1 the cushion or spring blade is .flexed to absorb the movement.

The spring blade is fashioned at its upper end with an inverted U-shape as 67 that straddles the upper end of the fixed rplate or of the partition, and of course by turning the bolt clock-wise the cushion is lifted. Thev spring blade is also retained with relation to fthe partition byumeans of a bolt 7 0 threaded l into the partition from the rear. Lock nuts 71 on the bolt 70 clamp the U-'shaped end on the partition, and the U-shaped end is slottedv at 72 to permit this adjustment. LThe-nu,-

meral in Figure4 indicates the position ofthe taper set cylinder with relation to Vthe dogging'- mechanism, but is not herein Assuming that the teeth of the dogs are to be set so that they will recede toward and to within 1/2 inch of the 'face plates with a cushioned stop to prevent wear and -tear of the parts, the nuts 39 on stem 36y areiirst loosened, kand the stem is pushed downwardly until the piston 35 contacts with the bot- `torn of the cylinder 25. The threadedjend of sov the stem 36 is then turnedin the L-shaped v f shackle to swingy the bell'crank levers 27 and 28y on their pivots, until, through the action of the bell cranks the dog holder advances its A dogs with their points about y; inch beyond the outer'faces of the face plates. Then the lock nuts 39 are tightened onthe stem and shackleto` hold the parts in adjusted position. f

The'adjustment of the piston in the cylinder 25 provides a space in the lower end of the cylinder, below the piston 35k in order that, after the dogs have been projected to engage a log, and are pulling the log toward the face plates 6, the cylinder and piston may act as a dash-pot or pneumatic cushion for the dogging mechanism, and the springblade 61 acts as a'mechanical cushion for the mechanism. f f c LThe vertical yadjustment or movement of the dog holder is limited by the use of a set bolt or stop ybolt 61a secured in the upper endA of the guide bar 13 of the dog holder.

Theknee is advanced and receded in well known manner, and as the reciprocating movements of the knee are usually abrupt,

these movements are cushioned` andy the f shocks are kabsorbed bythe pneumatically Y operating'receding mechanism indicated at .62,in Figure 1.

Having thus fully described my-invention,

what I claim as new and desire to secure by LettersPatent is 1. The combinationV with a vertically reciprocable dog holder, ofa spring operated v dog carried by the holder and relatively movable thereto, andco-acting means on the dog y and holder for moving the dog to draw a log toward the holder as the dog engages` with a log. Y f 1 42. The combination with a knee, a dog holder and a relatively movable dog carried by the holder,` of oo-aoting means on the dog and holder for drawing a log to the knee as the dog engages the log, and spring actuated means for returning the dog to normal position.

3. The combination with a dog holder and a dog mounted therein, of means within the holder for (3o-action with the dog for automatioally drawing the tooth of the dog toward the holder as the dog recedes within the holder under impact of its tooth with the 4. The combination with a dog holder having a pivot pin, or a slotted dog pivoted on the pin, a Cam face in the holder, a cam head on the dog for co-aetion with the face, and a return spring for the dog.

5. rThe combination with a knee, of a 'guide bar suspended within the knee, a vertically reeiprooable dog holder mounted on the guide bar, anti-frictionrollers carried by the holder for engagement with the knee, and a pair of dogs for selective use mounted in the holder.

6. The combination with an enclosing knee, of an upright guide bar mounted therein, a slotted dog' holder mounted on the guide bar and means for raising. or lowering the holder, a dogsupported Within the holder, and means oo-aoting with the dog for automatically drawing the tooth of the dog toward the knee as the holder is lowered.

In testimony whereof I my signature.

' GEORGE TANNER-.- 

